Many different types of memory modules are provided for use in computer technology, such as DIMMs and SIMMs, which must be interconnected to a motherboard or other printed circuit board. Typically such connectors include a plastic housing having a plurality of electrical contacts mounted on one or both sides of a slot which receives the memory module, the connector further including electrical contacts which interconnect traces on the memory modules with traces on the printed circuit boards. Many different types of memory module connectors are provided, some of which include edge-stamped contacts, that is, where the entire contact is stamped or etched in a plane from a blank of conductive material, where the plane of the material is disposed transverse to the slot in the housing. Another type of electrical terminal is the stamped and formed terminal, where the terminal is also formed from a blank of material where the plane of the original material is parallel to the slot receiving the memory module, but the terminals are stamped and formed to form the various contact portions.
U.S. Pat. No. 5,082,459 shows a representative socket, where the contacts are edge-stamped and where the contacts include alternative printed circuit board receiving contact positions, such that alternate contacts can have staggered printed circuit board contact portions so as to increase the side-to-side density of the contacts as well as the position of the throughholes on the printed circuit board. As mentioned above, such edge-stamped contacts are stamped in a single plane of the material, where the edge which is stamped or etched is the contact surface.
Alternatively, another style of contact is shown in U.S. Pat. No. 6,102,744, where the contacts are stamped and formed, where the contacts include both a memory module contact and a printed circuit board contact. Some of the contacts are stamped and formed so as to lie substantially in a single plane, whereas other contacts are formed with a printed circuit board portion staggered laterally away from the slot so as to stagger the electrical terminals.
It is the latter design, that is, the design as substantially shown in U.S. Pat. No. 6,102,744, which is incorporated in its entirety herein, to which the present invention relates. As shown in U.S. Pat. No. 6,102,744, the printed circuit board tine portions are profiled for receipt in printed circuit board throughholes, and are adapted for a soldered connection to the throughhole. While this design has proven quite adequate for such soldered connections, in the case of a compliant pin portion, that is, where the printed circuit board contact portion includes a configuration for interferingly fitting within a plated throughhole of a printed circuit board, the contacts having the staggered printed circuit board contact can be damaged.
The damage does not occur in the contacts where the printed circuit board portion is in the same plane as the memory module contact, because the column strength of the memory module contact itself is sufficiently rigid to withstand the force of the insertion of the terminal into the throughhole. However, when the contacts are staggered, the compliant pin portion does not have sufficient rigidity in the plane of the compliant pin portion to allow a force on that portion of the terminal and yet be inserted without damage to the contact and/or connector.
It is this problem which the present invention addresses.